Time-frequency component analyser and its application to brain oscillatory activity.

Ahmet Kemal Ozdemir; Sirel Karakaş; Emine D Cakmak; D Ilhan Tüfekçi; Orhan Arikan

doi:10.1016/j.jneumeth.2004.12.003

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Time-frequency component analyser and its application to brain oscillatory activity.

Ahmet Kemal Ozdemir·Sirel Karakaş·Emine D Cakmak·D Ilhan Tüfekçi·Orhan Arikan

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Abstract

Currently, event-related potential (ERP) signals are analysed in the time domain (ERP technique) or in the frequency domain (Fourier analysis and variants). In techniques of time-domain and frequency-domain analysis (short-time Fourier transform, wavelet transform) assumptions concerning linearity, stationarity, and templates are made about the brain signals. In the time-frequency component analyser (TFCA), the assumption is that the signal has one or more components with non-overlapping supports in the time-frequency plane. In this study, the TFCA technique was applied to ERPs. TFCA determined and extracted the oscillatory components from the signal and, simultaneously, localized them in the time-frequency plane with high resolution and negligible cross-term contamination. The results obtained by means of TFCA were compared with those obtained by means of other commonly used techniques of ERP analysis, such as bilinear time-frequency distributions and wavelet analysis. It is suggested that TFCA may serve as an appropriate tool for capturing the localized ERP components in the time-frequency domain and for studying the intricate, frequency-based dynamics of the human brain.

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Adolescent Adult Algorithms Brain Electroencephalography Evoked Potentials Female Fourier Analysis Humans Male Signal Processing, Computer-Assisted Time Factors Comparative Study Journal Article

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Ahmet Kemal Ozdemir, Sirel Karakaş, Emine D Cakmak, D Ilhan Tüfekçi, Orhan Arikan. 2005-06-30. Time-frequency component analyser and its application to brain oscillatory activity.. https://doi.org/10.1016/j.jneumeth.2004.12.003

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